The invention herein described was made in the course of a contract with the Naval Photographic Center, Anacostia, Maryland.
This invention is directed in general to automatic camera/processor/projectors and in particular to automatic camera/processor/projectors capable of providing rapid access to both a visual, e.g., a projected image corresponding to the original exposure, and the processed film which provides a record of the original exposure.
The novel camera/processor/projector of the instant invention takes advantage of new and simplified imaging systems which are capable of micro-image format of high density, continuous tone and high resolution. As will be explained further, preferred embodiments of the invention employ the process variations of these new systems to provide apparatus which can operate at from very low rates to camera framing rates suitable for motion picture reproduction.
The storage of information on micro-film evolved as one special application of conventional photographic technology. As a result, process orientation was based on the processing of photographic film, not on the processing of information. Adhering to the relatively complex darkroom technique used for conventional film, usual rapid processing equipment is engineered for the economics of high volume bulk processing of motion picture film. In rapid processing display systems such as those shown in the Tuttle U.S. Pat. No. 2,922,325 issued Jan. 26, 1960; or the Orlando U.S. Pat. No. 2,856,829, issued on Oct. 21, 1958 apparatus is shown for rapid camera processing systems using a chamber method of development. In these and other simple camera/processors, multiple low viscosity processing fluids are drawn from suitable containers across the emulsion of silver halide film either by positive pressure or a suction pump. Another developmental recorder/processor/projector system was described in an S.P.S.E. Conference in Chicago in May of 1967 (T. E. Gagnon "Rapid Reversal Process for CRT Images", S.P.S.E. Conference, Chicago; May 1967, p. 85). Negative images are created therein by a process similar to those described immediately above.
An example of the new imaging system of the type considered to be useful in the camera/processor/projector of the instant invention is that which is described in U.S. Pat. No. 3,520,681. Generally, according to an embodiment thereof, an imaging member comprising a conductive substrate with a layer of softenable (herein also intended to include soluble) material, containing photosensitive particles overlying the conductive substrate is imaged in the following manner: a latent image is formed on the member for example, by uniformly electrostatically charging and exposing it to a pattern of activating electromagnetic radiation. The imaging member is then developed by exposing it to a solvent which dissolves only the softenable layer. The photosensitive particles which have been exposed to radiation migrate through the softenable layer as it is softened and dissolved, leaving an image of migrated particles corresponding to the radiation pattern of the original on the conductive substrate. The image may then be fixed to the substrate. Through the use of various techniques, either positive to positive or positive to negative images may be made. Those portions of the photosensitive material which do not migrate to the conductive substrate may be washed away by the solvent with the softenable layer.
In general, three basic imaging members may be used. A layer configuration which comprises a conductive substrate coated with a layer of softenable material, and a fracturable and preferably particulate layer of photosensitive material or imbedded near the upper surface of the softenable layer; a binder structure in which the photosensitive particles are dispersed in the softenable layer which overcoats a conductive substrate; and an overcoated structure in which a conductive substrate is overcoated with a layer of softenable material followed by an overcoating of photosensitive particles and a second overcoating of softenable material which sandwiches the photosensitive particles.
The characteristics of the images produced in this new system are dependent on such process steps as charging, exposing and developing, as well as the particular combination of process steps. High density, continuous tone, and high resolution are some of the image characteristics possible. The image is generally characterized as a fixed or unfixed particulate image with or without a portion of the softenable layer in unmigrated portions of the layer left on the imaged member, which can be used in a number of applications such as microfilm, hard copy, optical masks, and strip-applications using adhesive materials.
Two camera/processors for migration imaging film are described in U.S. Pat. No. 3,528,355 and U.S. Pat. No. 3,542,465.